1. Field of the Invention
This invention relates generally to a picture communication apparatus and, more particularly, is directed to a picture communication apparatus having tablet means and which is capable of transmitting line drawing data generated by the tablet means together with video signals.
2. Description of the Prior Art
A picture communication apparatus has thus far been proposed to transmit a picture of the user together with an audio signal through, for example, an exclusive digital network line.
FIG. 1 shows an example of such a previously-proposed picture communication apparatus.
As shown in FIG. 1, in a picture communication apparatus 1, a picture of the user is taken by a camera apparatus 2 to produce a video signal. This video signal is supplied through a control circuit 3 to a data compressing and expanding circuit 4, in which it i compressed and is then transmitted to a transmission receiving apparatus (not shown). Alternatively, a picture of a document selected and positioned by the user is taken by a camera apparatus 5 and this picture is transmitted, instead of the picture of the user. Conversely, a video signal sent from a similar picture communication apparatus is expanded and converted to a video signal in the circuit 4. This converted video signal is then displayed on a predetermined display apparatus 6. Therefore, the users of two stations, each having a picture communication apparatus 1, can communicate with each other as though they were meeting in person while discussing drawings or the like.
Further, if the picture communication apparatus is combined with a tele-writing apparatus so that a line drawing inputted by a user terminal apparatus, for example, is independently transmitted to a transmission receiving apparatus, it becomes possible for the users to exchange their views while discussing drawings and the like between distant stations.
In the above-described picture communication apparatus, if a line drawing signal is added to the document signal and transmitted therewith, the picture communication apparatus can be utilized more effectively.